Frontotemporal Lobar Degeneration (FTLD): Review and Update for Clinical Neurologists

Background: Frontotemporal Dementia (FTD) is a heterogeneous group of disorders and the second most frequent cause of early onset dementia making it the highest number of inherited cases. Review Summary: FTD is characterized by considerable variability in clinical, genetic and histopathologic features. Patients may present symptoms ranging from behavioural disturbances to different language disorders, with or without motor neuron disorders or associated parkinsonism. Atrophy in frontal and temporal lobes is the most relevant radiological finding. In the last 10 years, the knowledge of this clinical entity has undergone remarkable changes both genetically and histopathologically, which have served to establish more consistent clinical criteria. Until now, 10 genes causative of FTLD have been described and up to four different proteins causative of atrophy have been detected in aggregates. Conclusion: This review is mostly addressed to clinicians and aims to provide basic knowledge of these neurodegenerative disorders and clarify the complex FTD scenario.